Image processing apparatus, reading apparatus, image forming apparatus, data management system and method

Abstract

To generate image data that can display a specified color intended to be displayed as a visible image.SOLUTION: An image processing apparatus according to the present invention has: an input unit that receives input of visible image data obtained by reading a subject with a sensor having sensitivity to light from a light source in a visible wavelength range and invisible image data obtained by reading the subject with a sensor having sensitivity to light from the light source in an invisible wavelength range; and an image processing unit that generates image data that displays, in a specified color, a portion of the visible data corresponding to a specified area being a portion having a predetermined absorptance or more in the invisible image data.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an image processing apparatus, a reading apparatus, an image forming apparatus, a data management system, and a method. [Background Art]

[0002] Conventionally, there is an OCR (Optical Character Recognition) technology that automatically extracts character information from a scanned image. In cases such as when a company name printed on a document is stamped with a seal, a color dropout function is used to remove a specific color to eliminate the seal impression, and then OCR is performed.

[0003] Patent Document 1 also discloses a technology in which character regions are determined using information from infrared light reading and visible light reading, black regions are determined using visible light information, and black character determination is performed based on these results. [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] However, when a seal impression is removed using a specific color, there is a problem that a black character portion is also colored with the specific color due to overlapping of the seal impression, and thus is removed together with the seal impression.

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an image processing apparatus, a reading apparatus, an image forming apparatus, a data management system, and a method that can generate image data capable of displaying a specified color desired to be displayed as a visible image. [Means for Solving the Problem]

[0006] To solve the above-mentioned problems and achieve the objective, the image processing apparatus according to the present invention is characterized by comprising: an input unit that receives visible image data obtained by reading a subject with a sensor sensitive to light from a light source in the visible wavelength range and invisible image data obtained by reading the subject with a sensor sensitive to light from a light source in the invisible wavelength range; and an image processing unit that generates image data that displays the portion of the visible image data that corresponds to a specified region which is the portion of the invisible image data with an absorption rate of a predetermined value or higher in a specified color. [Effects of the Invention]

[0007] According to the present invention, it is possible to generate image data that can display a specified color as a visible image. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 shows an example of the configuration of an image processing apparatus according to the first embodiment. [Figure 2] Figure 2 shows an example of using near-infrared light as invisible light. [Figure 3] Figure 3 shows the light absorption characteristics of the colorant. [Figure 4] Figure 4 shows an example of the configuration of a reading device. [Figure 5] Figure 5 shows an example of the configuration of the control block of the reading device. [Figure 6] Figure 6 schematically shows the configuration for correcting black text during shadow removal. [Figure 7] Figure 7 is an explanatory diagram of the image processed in the decolorization area. [Figure 8] Figure 8 shows an example of the configuration of a reading device according to a modified example 1 of the embodiment. [Figure 9] Figure 9 shows an example of the configuration of a reading device according to a modified example 2 of the embodiment. [Figure 10] Figure 10 shows an example of the configuration of a reading device according to a modified example 3 of the embodiment. [Figure 11] FIG. 11 is a diagram showing an example of an embodiment to which Modification 3 is applied. [Figure 12] FIG. 12 is an explanatory diagram of a black character region determining unit according to Modification 4. [Figure 13] FIG. 13 is an explanatory diagram for determining a threshold in the black character region determining unit according to Modification 5. [Figure 14] FIG. 14 is an explanatory diagram of a configuration for determining a threshold in the black character region determining unit. [Figure 15] FIG. 15 is a diagram showing an example of a configuration of a black character region determining unit according to Modification 6. [Figure 16] FIG. 16 is a diagram showing an example of processing in a desaturation processing unit according to Modification 7. [Figure 17] FIG. 17 is a diagram showing an example of a UI setting screen for adjusting a luminance component in desaturation processing. [Figure 18] FIG. 18 is an explanatory diagram of a configuration for removing a specified color such as a ruled line. [Figure 19] FIG. 19 is a diagram showing an example of a configuration of an image correction unit according to Modification 8. [Figure 20] FIG. 20 is a diagram showing an example of a configuration according to Modification 9. [Figure 21] FIG. 21 is a diagram showing an example of a configuration according to Modification 10. [Figure 22] FIG. 22 is a diagram showing an example of a configuration of a system including an image processing apparatus according to a second embodiment. [Figure 23] FIG. 23 is a diagram showing an example of a configuration of an image forming apparatus according to a third embodiment. [Figure 24] FIG. 24 is a comparative diagram when a specific color is removed by a conventional method. MODE FOR CARRYING OUT THE INVENTION

[0009] Hereinafter, embodiments of an image processing apparatus, a reading apparatus, an image forming apparatus, a data management system, and a method will be described in detail with reference to the accompanying drawings.

[0010] (First Embodiment) FIG. 1 is a diagram showing an example configuration of an image processing apparatus according to a first embodiment. The image processing apparatus 00 includes an input unit 1a, an image processing unit 2a, an identification unit 3a, and an output unit 4a. The input unit 1a inputs a subject image, which includes visible image data D1 of the subject and invisible image data D2 of the subject. The identification unit 3a identifies a black character region based on the invisible image data D2 input from the input unit 1a. Note that the "black character region" corresponds to a "specified region", and is described herein as a region where black (a specified color) characters are used for ease of explanation. The "black character region" is not limited to this, and may be any region printed with black. The image processing unit 2a generates image data D3 that causes a portion corresponding to the black character region in the visible image data D1 to be displayed in black, based on the visible image data D1 input from the input unit 1a and the black character region identified by the identification unit 3a. The output unit 4a outputs the image data D3. The output destination of the output unit 4a may be appropriately determined, for example, it may be a display unit of the image processing apparatus 00 or an external device connected to the image processing apparatus 00. As the first embodiment, an example where the image processing apparatus 00 is applied to a reading apparatus will be described. First, the overall configuration of the reading apparatus will be shown, and the process of generating image data D3 that causes a portion corresponding to the black character region in the visible image data D1 of the subject to be displayed in black in the reading apparatus will be described. Note that in the reading apparatus, an imaging unit corresponds to the input unit 1a. The configuration of the reading apparatus shown herein is an example, and any reading apparatus that reads a subject image by irradiating the subject with light from a light source and imaging light from the subject with the imaging unit may be used.

[0011] Furthermore, the processing performed by the image processing unit 2a and the identification unit 3a corresponds to the processing for removing imprints from the subject image, which will be described later. Some or all of this processing may be performed within the reading device, or it may be performed by an image processing device provided separately from the reading device, for example, by inputting the subject image read by the reading device. If the entire process is performed by the image processing device, the image processing device may input the subject image stored in a server or memory. In this embodiment, an example is shown in which the image processing device is applied to the reading device, but the image processing device can be provided separately from the reading device.

[0012] In the following, the subject may be referred to as the "object to be read." The object to be read is an area where black text is printed, and the object to be removed, such as a seal impression, is superimposed on it. As an example, this refers to paper documents such as various certificates, documents, or forms with seals stamped on them, but the object to be removed is not limited to seal impressions. Also, the object to be read is not limited to paper documents.

[0013] Furthermore, "visible image data" refers to image data read by a sensing device such as an image sensor that is sensitive to light from a light source in the visible wavelength range (visible light). Conversely, "invisible image data" refers to image data read by a sensing device such as an image sensor that is sensitive to light from a light source in the invisible wavelength range, such as infrared (including near-infrared) or ultraviolet light. Below, near-infrared image data (hereinafter simply referred to as near-infrared image) is shown as an example of "invisible image data," but it is not limited to near-infrared images. As an example, an example of using near-infrared light as invisible light is shown (see Figure 2). As shown in Figure 2, a typical silicon image sensor is sensitive in the near-infrared region (approximately 750nm to 1100nm). Therefore, since conventional general-purpose image sensors can be used, it is possible to implement it with a simple configuration. Black ink, black toner, or graphite pencils used for black text contain carbon. Carbon has the characteristic of absorbing light in the visible and infrared regions. Therefore, it can be read as black in the visible and infrared regions. On the other hand, color inks and CMY color toners have the characteristic of transmitting light in the infrared region. This characteristic is shown in Figure 3. The horizontal axis represents the wavelength of light, and the vertical axis represents the light absorption rate. In Figure 3, black refers to the color of a material containing carbon as described above, gray refers to the color printed by thinning with gray ink or black toner, and color mixed refers to a color created by mixing CMY colors (hereinafter referred to as color mixed black). Color mixed black absorbs light in the visible region but transmits light in the near-infrared region, so it can be read as white in the near-infrared region. Here, the part (pixel) where the absorption rate is above a predetermined value across the visible and invisible regions (near-infrared region) is defined as the "designated region." As an example, a color (pixel) with an absorption rate of 40% or more is designated as the designated region (black region).

[0014] Figure 4 shows an example of the configuration of the reading device. The main body 10 of the reading device 1 has a contact glass 11 on its upper surface and an imaging unit inside the main body 10. Inside the main body 10 are a light source 13, a first carriage 14, a second carriage 15, a lens unit 16, an image sensor 17, and the like. The first carriage 14 has a light source 13 and a reflective mirror 14-1, and the second carriage 15 has reflective mirrors 15-1 and 15-2. The main body 10 also includes a control board. The control board is the control unit 300 shown in Figure 5, which controls the entire reading device 1.

[0015] The control board moves the first carriage 14 and the second carriage 15, irradiating them with light from the light source 13, and sequentially reads the reflected light from the object to be read, placed on the contact glass 11, using the image sensor 17. Due to the irradiation of light from the light source 13, the light reflected from the object to be read is reflected by the mirror 14-1 of the first carriage 14 and the mirrors 15-1 and 15-2 of the second carriage 15, and enters the lens unit 16. The light emitted from the lens unit 16 forms an image on the image sensor 17. The image sensor 17 receives the reflected light from the object to be read and outputs an image signal. The image sensor 17 is an image sensor such as a CCD (Charge Coupled Device) or CMOS (Complementary MOS), and corresponds to the reading unit that reads the image of the object to be read.

[0016] The light source 13 is equipped with a visible light source and a near-infrared light source. The image sensor 17 has a first image sensor that receives reflected visible light irradiated onto the reading target and outputs an image, and a second image sensor that receives reflected near-infrared light irradiated onto the reading target and outputs an image. An image received by irradiating the reading target with visible light is called a visible image, and an image received by irradiating the reading target with near-infrared light is called a near-infrared image. Although a visible light source and a near-infrared light source are provided separately, a single light source may also be used.

[0017] The first and second image sensors may be configured as a single image sensor, or each image sensor may be provided separately, as long as they are capable of outputting a visible image and a near-infrared image, respectively.

[0018] The reference whiteboard 12 is a component used for white correction.

[0019] The reading device 1 shown in Figure 4 is equipped with an ADF (Automatic Document Feeder) 20. When one side of the ADF 20 is lifted upwards, it opens, exposing the surface of the contact glass 11. The user places the object to be read on the contact glass 11, lowers the ADF 20, and presses the ADF 20 against the surface of the contact glass 11 from the back of the object to be read. When the scan start button is pressed, the first carriage 14 and the second carriage 15 are driven in the main scanning direction and the sub-scanning direction, and the entire object to be read is scanned.

[0020] In addition to the method of setting the object to be read on the contact glass 11 and reading it, the object to be read can also be read by the following method. The ADF 20 can also read the object to be read using a sheet-through method. In the ADF 20, the pickup roller 22 separates the bundle of objects to be read from the tray 21 of the ADF 20 into individual sheets, and through the control of various transport rollers 24, etc., one or both sides of the object to be read is read as it is transported along the transport path 23 and discharged into the output tray 25.

[0021] The reading of the object to be read using the sheet-through method by the ADF20 is performed through the reading window 19. In this example, the first carriage 14 and the second carriage 15 are moved to a predetermined home position and fixed, and as the object to be read passes between the reading window 19 and the background part 26, the light from the light source 13 is shone on the surface of the object to be read, which is facing the reading window 19, to read the image. The reading window 19 is a slit-shaped reading window provided in a part of the contact glass 11. The background part 26 is a background material.

[0022] When the ADF20 performs double-sided reading of the object to be read, after the object passes through the reading window 19, the reading module 27 of the second reading means, which is provided on the back side of the object, reads the back side. The reading module 27 has an illumination unit including a light source and a contact-type image sensor, which is the second reading unit, and the contact-type image sensor reads the reflected light of the light irradiated on the second surface. In addition, this light source may also be provided with a visible light source and a near-infrared light source so that visible images and near-infrared images can be read. The background member 28 is a density reference member.

[0023] Next, the configuration of the control block of the reading device 1 will be described. Figure 5 shows an example of the configuration of the control block of the reading device 1. As shown in Figure 5, the reading device 1 has a control unit 300, an operation panel 301, various sensors 302, a scanner motor 303, various motors 304 for the transport path, a drive motor 305, an output unit 306, and an imaging unit 40. Various other control targets are also connected. The various sensors 302 are sensors that detect the object to be read. The scanner motor 303 is a motor that drives the first carriage 14 and the second carriage 15 of the main body 10. The various motors 304 for the transport path are various motors provided in the ADF 20. The output unit 306 corresponds to the output interface for the output unit 4a to output image data to an external device. The output interface may be an interface such as USB or a communication interface that connects to a network.

[0024] The operation panel 301 is, for example, a touch panel type liquid crystal display device. The operation panel 301 receives input operations from the user, such as various settings and read execution (start scan), via operation buttons or touch input, and transmits the corresponding operation signals to the control unit 300. The operation panel 301 also displays various display information from the control unit 300 on its display screen. For example, the operation panel 301 is equipped with various setting buttons for the user to remove the impression of a seal pressed on a subject, and when a setting button is pressed, it instructs the control unit 300 to make the setting. The setting screen on the display screen may allow the user to select whether or not to remove the seal impression. Alternatively, the system may be configured so that the seal impression is always removed when the scan execution button is pressed. Furthermore, various data used for seal impression removal may be saved to an external memory or output to an external device.

[0025] The imaging unit 40 corresponds to the input unit 1a. The imaging unit 40 includes a light source unit 401, a sensor chip 402, an amplifier 403, an A / D converter 404, an image correction processing unit 405, a frame memory 406, an output control circuit 407, and an I / F circuit 408. Images read from the object to be read are output frame by frame from the output control circuit 407 to the control unit 300 via the I / F circuit 408. Each sensor chip 402 is a pixel sensor of the image sensor 17. The light source unit 401 is the light source 13.

[0026] The imaging unit 40 is driven by the controller 307. For example, the imaging unit 40 lights up the light source unit 401 based on a lighting signal from the controller 307 and illuminates the object to be read with visible light and near-infrared light at the set timing. The imaging unit 40 also converts the light from the object to be read, which is imaged on the sensor surface of the image sensor 17, into an electrical signal using each sensor chip 402 and outputs it.

[0027] The imaging unit 40 amplifies the pixel signals output from each sensor chip 402 using an amplifier 403, converts them from analog signals to digital signals using an A / D converter 404, and outputs pixel level signals. The image correction processing unit 405 performs image correction processing on the output signals from each pixel. For example, the image correction processing unit 405 performs shading correction on the output signals from each pixel.

[0028] After image correction processing, each data point is stored in the frame memory 406, and the stored read images are transferred to the control unit 300 via the output control circuit 407 and the I / F circuit 408.

[0029] The control unit 300 is equipped with a CPU (Central Processing Unit), memory, etc., and the CPU controls the entire device to perform reading operations on the object to be read, and to perform processing such as seal impression removal on the read image obtained from the reading operation. The control unit 300 includes a processing unit 30 and a black text area determination unit 32. The processing unit 30 and the black text area determination unit 32 can be implemented by a functional unit that is performed by the CPU executing a predetermined program. Alternatively, they can also be implemented by hardware such as an ASIC (Application Specific Integrated Circuit).

[0030] (Regarding the removal of the seal impression) Next, we will explain the removal of seal impressions in detail. Using documents as examples of reading targets, we will show the configuration and method for removing seal impressions from scanned images of those documents using a specified color removal function that removes specific colors. Note that black ink, black toner, or graphite pencils used for black text contain carbon. Carbon has the characteristic of absorbing light in the infrared region. On the other hand, color inks and CMY color toners have the characteristic of transmitting light in the infrared region. Colors other than black, such as color inks and CMY color toners, are sometimes referred to as "color ***" such as color ink or color toner.

[0031] Therefore, when near-infrared light is shone on the object to be read and a near-infrared image is read, the near-infrared light is transmitted through the parts of the paper medium that are formed by color components, and then reflected by the paper medium, causing the paper medium to be read as a bright color such as white with a high luminance value.

[0032] In contrast, black printed areas absorb light from both visible and near-infrared light. Because near-infrared light is absorbed in black text areas, the amount of reflected light is small, and it is read as black with a low brightness value. Even in black text areas where the seal impression overlaps, near-infrared light passes through the seal impression, but the near-infrared light is absorbed in the black text area where the seal impression overlaps, so even if it appears reddish under visible light, it is read as black in the near-infrared image. Furthermore, in black text areas, the parts where the seal impression does not overlap are read as black even under visible light.

[0033] Figure 6 is a schematic diagram showing the configuration for correcting black text during shadow removal. The imaging unit 40 includes the visible light source 13-1 and visible image sensor 17-1 described in Figure 5, and the near-infrared light source 13-2 and near-infrared image sensor 17-2, respectively. The imaging unit 40 irradiates the object to be read with light from the visible light source 13-1, receives the reflected light from the object to be read with the visible image sensor 17-1, and outputs a visible image (RGB image as an example). The imaging unit 40 also irradiates the same object to be read with light from the near-infrared light source 13-2, receives the reflected light from the object to be read with the near-infrared image sensor 17-2, and outputs a near-infrared image (NIR image). The imaging unit 40 can read both a visible image and a near-infrared image from the same object to be read simultaneously. Furthermore, if the object being read is the same, the imaging unit 40 does not need to read both the visible image and the near-infrared image simultaneously; they can be read at different times as long as the positions of the respective objects match.

[0034] The processing unit 30 includes a color-decolorization processing unit 31 and a black text area determination unit 32. The color-decolorization processing unit 31 and the black text area determination unit 32 are shown together as the color-decolorization unit 30-1. In this configuration, the color-decolorization processing unit 31 of the processing unit 30 corresponds to the image processing unit 2a (see Figure 1), and the black text area determination unit 32 corresponds to the identification unit 3a (see Figure 1). The decolorization unit 30-1 receives the near-infrared image captured by the imaging unit 40. The black character region determination unit 32 identifies the black character region from the near-infrared image and outputs the pixel positions of the identified black character region to the decolorization processing unit 31. The decolorization processing unit 31 performs a process to decolorize the corresponding color pixels on the visible image based on the pixel positions of the black character region identified by the black character region determination unit 32, thereby outputting an R'G'B' image with the target color pixels decolorized as image data D3 that displays the part corresponding to the black character region in black. The R'G'B' image corresponds to the first processed image.

[0035] Here, the RGB image consists of a Red (R) version image, a Green (G) version image, and a Blue (B) version image, and the decolorization processing unit 31 decolorizes the target color pixels of the Red (R), Green (G), and Blue (B) versions of each image. The R'G'B' image consists of a Red (R') version image, a Green (G') version image, and a Blue (B') version image.

[0036] Here, pixels corresponding to chromatic colors, excluding achromatic colors, are called color pixels. When the seal impression overlaps with black text, the color changes, so by making those color pixels achromatic, the black text portion whose color has changed is restored to black. This makes it possible to restore the black text portion, both where the seal impression overlaps and where it does not, to black without any breaks.

[0037] Figure 7 is an explanatory diagram of the image processed by the decolorization unit 30-1. As an example, the document used for reading is one in which a red seal impression is superimposed on part of the black text "Sample Seal of Corporation".

[0038] Figure 7(a) shows the visible image M10 input to the decolorization unit 30-1. In the visible image M10, the image is in the same state as when a person sees the original document under visible light; that is, a portion of the black text "Corporate Seal Sample" t1 is superimposed with a vermilion seal impression t2, and the parts of the black text area where the seal impression t2 overlaps are colored vermilion by the seal impression t2. In this state, even if OCR is performed, it is not possible to recognize all of the characters in "Corporate Seal Sample".

[0039] Figure 7(b) shows the near-infrared image M20 input to the decolorization unit 30-1. In the near-infrared image M20, the same black text "Co., Ltd. Seal Impression Sample" t1 as in the visible image M10 is shown all in black and stands out. The black text portion where the seal impression t2 overlaps stands out in black, just like the other black text portions, due to the irradiation with near-infrared light. By using the near-infrared image M20, the black text region determination unit 32 can identify the black text portion where the seal impression t2 overlaps as a black text region, just like the other black text portions.

[0040] Figure 7(c) is the first processed image M11, which is the image after the color pixels in the black text area of ​​"Corporate Seal Impression Sample" t1, which had a reddish tint due to the overlapping seal impression t2 in the visible image M10, have been decolorized. In the visible image M10, the black text area of ​​"Corporate Seal Impression Sample" t1, where the seal impression t2 overlapped, had a reddish tint, but after decolorization, it becomes black, and as in the first processed image M11, "Corporate Seal Impression Sample" t1 is restored in black without any breaks, both in the areas where the seal impression overlaps and the areas where it does not.

[0041] Figure 7(d) shows image M12 after removing the seal impression, when a specific color is removed using the first processed image M11. By removing the vermilion color of the seal impression t2, the seal impression t2 is removed, but the black text "Seal Impression Sample Co., Ltd." t1 remains clean without blurring or loss.

[0042] In contrast, if a specific color is removed using the conventional method, this does not occur; the black text "Sample Company Seal" becomes blurred or missing, making OCR recognition of that portion difficult (see Figure 24).

[0043] In this embodiment, a colorless processing unit 31 and a black character area determination unit 32 are provided to determine black character areas from a near-infrared image obtained by reading a visible image simultaneously, and the color pixels at the same positions on the visible image that have been determined to be black character areas are colorless.

[0044] As a result, black text that has been colored by overlapping seal impressions is restored to black, thus suppressing blurring or loss of black text even when seal impression removal is performed in a later stage by removing specific colors. Consequently, the OCR recognition rate can also be improved.

[0045] (Modification 1 of the embodiment) This section describes the case where a decolorized RGB image is output to an external device outside of the reading device 1. While the same applies to other forms and modifications described later, explanations that overlap with the embodiment will be omitted as appropriate, and the main differences will be described.

[0046] Here, the connection between the reader 1 and the external device may be either wired or wireless. Furthermore, the reader 1 and the external device may be connected via a USB or other connection cable, or via a communication network using a communication interface.

[0047] External devices include, for example, information processing devices with a computer configuration such as a user PC, or server devices. These devices are equipped with a CPU, which executes predetermined programs to perform tasks such as shadow removal and OCR processing from decolorized RGB images. Output is sent to the external device from the output unit 306 (see Figure 5).

[0048] Figure 8 shows an example of the configuration of a reading device according to Modification 1 of the embodiment. An image correction unit 33 is provided in the processing unit 30. The image correction unit 33 performs filtering and color correction processing on the R'G'B' image output from the decolorization unit 30-1 and functions to output the outR'G'B' image to an external device. The image output to the external device is the data before the removal of imprints by removing specific colors.

[0049] As described above, in the configuration of Modification 1, the reader 1 can output an outR'G'B' image that can be treated in the same way as a normal RGB scanner image. Since the outR'G'B' image has been decolorized in the areas of black text where the seal impression overlaps, even if post-processing is performed in a later stage, the external device in the later stage can treat it in the same way as an RGB scanner image of other document images that do not originally have a seal impression. In addition, since the outR'G'B' image is output with a visual quality that is indistinguishable from a normal RGB scanner image, it can be used as an image for archival purposes.

[0050] As a post-processing step, when performing OCR using an external device, the black text areas where the seal impression overlaps are decolorized. Therefore, even after removing the seal impression by removing specific colors, the text is less likely to become blurred or missing, thus reducing the likelihood of OCR misrecognition.

[0051] (Modified example 2 of the embodiment) This section describes a configuration for outputting a colorless RGB image to an external source as an image specifically for OCR. Figure 9 shows an example of the configuration of a reading device according to a modified example 2 of the embodiment.

[0052] As shown in Figure 9, the image correction unit 33 is equipped with a seal impression removal unit 34 and a monochromatic processing unit 35. The seal impression removal unit 34 removes the seal impression by removing a specific color from the R'G'B' image that has undergone achromatic processing. The monochromatic processing unit 35 performs K monochromatic processing on the R'G'B'' image after seal impression removal to facilitate OCR recognition. The image after K monochromatic processing is output to the outside from the image correction unit 33. The image after monochromatic processing corresponds to the "second processed image".

[0053] In the configuration of Modified Example 2, the seal impression can be removed within the same system using optimal removal parameters for a decolorized R'G'B' image. Therefore, for example, it is possible to use removal parameters that make color determination easier, assuming that black text has been decolorized, and even slightly faded seal impressions can be targeted for removal. Consequently, an improvement in the accuracy of seal impression removal is expected in the configuration of Modified Example 2.

[0054] (Modification 3 of the embodiment) When performing OCR on documents, there are cases where the original document is stored as evidence. In such cases, it is necessary to retain information such as the seal impression on the document. Images that have undergone processing optimized for OCR have had unnecessary information other than text removed, making them unsuitable for storage as evidence.

[0055] Therefore, in Modification 3, we show a configuration that can output not only the monochrome OCR image specifically for OCR shown in Modification 2, but also the original image that has not undergone OCR processing.

[0056] Figure 10 shows an example of the configuration of a reading device according to a modified example 3 of the embodiment. As shown in Figure 10, the RGB image output from the visible image sensor 17-1 is output to both a processing unit for outputting an image for storage and a processing unit for outputting an image for OCR. The processing unit for outputting an image for storage corresponds to the second image processing unit 36 ​​in Figure 10. The second image processing unit 36 ​​performs image correction processing for storage on the RGB image output from the visible image sensor 17-1 and outputs an RGB image for storage. The configuration of the processing unit for outputting an image for OCR is the same as the configuration of the color-decolorization unit 30-1 and the image correction unit 33 shown in Figure 9, so a description is omitted.

[0057] In the configuration of Modified Example 3, for a single object to be read, both a save image and an OCR image are output in a single reading. This allows the user to acquire both the save image and the OCR image together using a PC or other device, eliminating the need to obtain them separately.

[0058] In Figure 10, the configuration of the decolorization unit 30-1 and the image correction unit 33 shown in Figure 9 is applied to the processing unit for outputting an OCR image, but this is just one example and is not limited to this configuration. For example, the configuration shown in Figure 8 may be used to output an outR'G'B' image. The outR'G'B' image is an image that has undergone decolorization processing but has not had any specific colors removed.

[0059] (Example of Modification 3) Next, an example applying Modification 3 is shown. Figure 11 is a data management system that applies the device configuration shown in Figure 10. The PC or server is equipped with a storage device and stores and manages the storage image data and OCR image data transmitted from the processing unit 30 as a set. The storage image data and OCR image data are linked by names that make their relationship clear and are managed in a common storage device. By using this data management system, it is possible to prevent the loss of the original image data that serves as the source for the OCR image data, and management becomes easier by managing them in a common location.

[0060] (Modification 4 of the embodiment) Next, as Modification 4, we will describe a modified method for determining the black text area in the near-infrared image when the seal shadow is faintly visible.

[0061] Figure 12 is an explanatory diagram of the black text area determination unit 32 according to the modified example 4. As shown in Figure 12(a), the black text area determination unit 32 has a binarization processing unit 3000. Figure 12(b) is an example of a near-infrared image in which a seal impression is faintly visible. As shown in Figure 12(b), the seal impression t2 is faintly visible in the near-infrared image. As already explained, the black text area is represented in black because near-infrared light is absorbed and the amount of light received by the near-infrared sensor is small. On the other hand, although the amount of near-infrared light absorbed by colored areas such as seal impressions is small, they have a small amount of absorption characteristics and may be represented in light gray as shown in Figure 12(b).

[0062] In such cases, it is difficult to identify the black text region t1 from the near-infrared image alone. Therefore, binarization is performed. The binarization processing unit 3000 shown in Figure 12(a) performs binarization by comparing the pixel values ​​of the input infrared image with a threshold value, thereby classifying pixels that take values ​​on the black side as pixels of the black text region and pixels that take values ​​on the white side as pixels of the non-black text region. Since the pixels of the print t2 are not white, a threshold is set between the pixel value of the black text region t1 and the pixel value of the print t2, so that pixels consisting only of the print t2 are classified as non-black text regions. This threshold can also be used to distinguish between black from three-color mixing.

[0063] The black character area determination unit 32 performs binarization processing in this manner and outputs the results for black character pixels and non-black character pixels to the decolorization processing unit 31.

[0064] Thus, using binarization in black text area detection makes it easier to separate the black text area from the colored areas such as seal impressions.

[0065] (Modification of the embodiment 5) Next, as Modification 5, we will describe a modification in which a threshold is determined in the black text area determination unit.

[0066] Figures 13 and 14 are explanatory diagrams illustrating the configuration for determining a threshold value in the black text area determination unit 32 according to the modified example 5.

[0067] Figure 13(a) is an example of a document where black text and a seal impression overlap. The overlapping area between the black text and the seal impression is shown in magnification. Figure 13(b) is an RGB visible image of the document in Figure 13(a), and Figure 13(c) is a near-infrared image of the document in Figure 13(a).

[0068] In reading device 1, both RGB images and near-infrared images are read using the same optical system (lenses, mirrors, etc.). Therefore, if adjustments are made to match the image quality of the RGB image, the near-infrared image will be more blurred than the RGB image, as shown in Figures 13(b) and 13(c).

[0069] In other words, as shown in Figure 13(d), when examining the pixel changes near the edges of black text, the near-infrared image shows more rounded pixel value changes compared to the RGB image. In this case, if the binarization threshold for determining the black text area in the near-infrared image is taken near where the change from the background level of the original document occurs, it can be seen that the position of the black text edges shifts between the near-infrared image and the RGB image. In the near-infrared image, the black text area is determined to be thicker, and as a result, there is a possibility that some of the imprint outside the edge of the black text area in the RGB image may be rendered colorless.

[0070] Therefore, as shown in Figure 14(a), a scalp level setting unit 37-1, a black level setting unit 37-2, and a threshold determination unit 3500 are provided.

[0071] As settings and design values ​​in the user interface (UI), the system pre-stores settings for scalp level and black level, and the threshold determination unit 3500 determines the threshold based on the settings of the scalp level setting unit 37-1 and the black level setting unit 37-2.

[0072] As shown in Figure 14(b), in the transition of an edge from a certain skin tone level to a certain black level, the intermediate region of the level change between them remains constant regardless of the degree of blurring in the image. Therefore, by setting the threshold to an intermediate level between the skin tone level and the black level, the error in the position of the black text region determined in the near-infrared image and the black text region in RGB images with different degrees of blurring can be minimized.

[0073] (Modification 6 of the embodiment) Next, as Modification 6, we will describe a second modification in which a threshold is determined in the black text area determination unit. In Modification 5, the threshold was determined using setting values ​​and design values ​​set from the UI. However, the background level and the black level of the text differ depending on the input image. Even within a single document, the background color and density, and the density of the black text may differ depending on the location. With the pre-set values, there are cases where the background level is darker than expected and is detected as black text, for example, and this cannot be handled. Therefore, Modification 6 shows a configuration in which the system automatically detects the background level and black level from the image and determines the threshold.

[0074] Figure 15 shows an example of the configuration of the black text area determination unit 32 according to Modification 6. As shown in Figure 15, the black text area determination unit 32 is provided with a background level detection unit 3600 and a black level detection unit 3700.

[0075] The scalp level detection unit 3600 sets a target pixel in the near-infrared image, and then references surrounding pixels within an arbitrary range to detect the scalp level near the target pixel.

[0076] The black level detection unit 3700 refers to surrounding pixels within an arbitrary range for the pixel of interest and detects the black level of black characters present near the pixel of interest.

[0077] The threshold determination unit 3500 determines a threshold using the scalp level and black level detected by the scalp level detection unit 3600 and the black level detection unit 3700. The binarization processing unit 3000 performs binarization processing using that threshold.

[0078] In this configuration, since the detection of skin tone level and black level is performed for each input image, even if the skin tone level or the black level of text differs depending on the input image, binarization can be performed with an appropriate threshold depending on the input image. Furthermore, this configuration allows for the detection of both background and black levels for each area of ​​a single image. By performing this area-by-area detection, it becomes possible to use different optimal thresholds for each area during binarization, enabling highly accurate extraction of black text areas.

[0079] (Modification 7 of the embodiment) Next, as a modified example 7, an example of the processing performed by the decolorization processing unit 31 is shown.

[0080] Figure 16 shows an example of processing in the decolorization processing unit 31 according to Modification 7. As shown in Figure 16, the decolorization processing unit 31 performs RGB to YUV conversion 3101, decolorization processing 3102, and YUV to RGB conversion 3103. Here, RGB to YUV conversion 3101 corresponds to the "luminance color difference conversion unit," and YUV to RGB conversion 3103 corresponds to the "RGB conversion unit."

[0081] The RGB to YUV converter 3101 converts an input RGB image into a YUV signal (luminance chrominance signal).

[0082] In the decolorization process 3102, the input YUV signal is corrected for pixels located in black character regions by referring to the result of the black character region determination, and decolorization is performed. On the other hand, pixels located in non-black character regions are output without decolorization.

[0083] The YUV to RGB converter 3103 performs an inverse conversion to convert the decolorized YUV signal back to an RGB image, outputting the decolorized R'G'B' image to the next stage.

[0084] (Example of calculation process)

[0085] An example of the calculation process of the decolorization processing unit 31 is shown below. Black text area: out_Y = in_Y , out_U=0 , out_V=0 Non-black character area: out_Y = in_Y , out_U=in_U , out_V=in_V

[0086] This process converts the input image to a luminance-chrominance signal like YUV, which allows for adjustment of saturation while maintaining the luminance component. This enables image desaturation while preserving the density of black text in the input image.

[0087] While this example demonstrates conversion to a YUV signal, it is not limited to this. Any format other than YUV is acceptable, as long as the image can be processed using luminance and chrominance conversion. For example, YCbYCr.

[0088] (Adjustment of luminance component) The adjustment of luminance components in the decolorization process 3102 will now be explained. The decolorization processing unit 31 may switch the luminance components according to user settings when performing the decolorization process.

[0089] Figure 17 shows an example of a UI setting screen for adjusting the luminance component of the decolorization process 3102. The UI setting screen 1000 has a setting confirmation tab 1001, and when the setting confirmation button 1001 is touched, the setting information shown in Figure 17 is displayed.

[0090] The settings information displays the settings corresponding to the mode setting of character 1002. The adjustment information 1003 is the adjustment information for adjusting the brightness component.

[0091] The adjustment information 1003 has adjustment buttons to adjust the brightness of black or non-black text, such as maintaining the original brightness, making it lighter, or making it darker. The user adjusts the brightness component when they want to emphasize the blackness of black text, for example.

[0092] The UI settings screen 1000 accepts settings for the brightness components of black and non-black text via these adjustment buttons, and when the start button 1004 is touched, it sets those settings in the colorless processing unit 31.

[0093] For example, if you set black text to "dark" and non-black text to "light," the output value is adjusted by multiplying the Y component by a coefficient, as shown in the following calculation example.

[0094] (Example of calculation process) Black text area: out_Y = in_Y*0.9 , out_U=0 , out_V=0 Non-black character area: out_Y = in_Y*1.1 , out_U=in_U , out_V=in_V

[0095] This adjustment information allows not only for colorless rendering but also for adjusting the intensity of black or non-black text to the user's desired level.

[0096] (Modification 8 of the embodiment) Next, as a modified example (modification 8), a configuration for removing specified colors such as grid lines will be described.

[0097] Figures 18 and 19 are explanatory diagrams of a configuration for removing specified colors such as ruled lines. As shown in Figure 18(a), forms often have ruled lines t3 drawn to clearly define the input fields. Due to misalignment of the printed position of type or misalignment of the handwritten input position, the black text area t1 of the entered black text may overlap with the ruled line t3. If OCR is performed in this state, the ruled line t3 will interfere and the text information cannot be properly extracted. Therefore, as shown in Figure 18(b), a setting unit 1003 is provided in the UI setting screen 1000 to instruct the removal of a specified color. The setting unit 1003 is a setting unit for the user to specify the color they want to remove. In the example shown in Figure 18(b), color specification buttons such as chromatic colors, red, green, blue, cyan, magenta, and yellow are provided, and the user selects the color they want to remove from among them. Note that the types of colors and the method of specifying colors are not limited to this and may be modified as appropriate.

[0098] Figure 19 shows an example of the configuration of the image correction unit 33 according to Modification 8. As shown in Figure 19, the image correction unit 33 is provided with a specified color removal unit 38.

[0099] The specified color removal unit 38 removes the specified color received from the user via the UI setting screen 1000 by the UI 50 from the R'G'B' image that has been decolorized by the decolorization unit 30-1.

[0100] For example, to remove grid lines, the user specifies a color corresponding to the grid line color in the settings unit 1003, and the grid lines are removed by removing that specified color.

[0101] This configuration makes it possible to remove lines and other elements, which helps to reduce character recognition errors during OCR recognition.

[0102] (Modification 9 of the embodiment) This configuration shows how to output an image for OCR as a multi-level image after monochrome processing.

[0103] Figure 20 shows an example of the configuration according to Modification 9. As shown in Figure 20, when outputting a monochromatic image from the monochromatic processing unit 35, a multi-level monochromatic image is output instead of a binary image. A multi-level monochromatic image is, for example, a grayscale image.

[0104] By outputting multiple values ​​in this way, detailed information surrounding the characters can be preserved and passed to subsequent OCR software. If the subsequent OCR software performs advanced binarization processing, this processing can be utilized, leading to further improvements in OCR recognition accuracy.

[0105] Furthermore, although Figure 20 shows a single-image output configuration with only a monochrome image, it can also be applied to outputting multi-image images including RGB images, as shown in Figure 10.

[0106] (Modified example 10 of the embodiment) This configuration describes a method for outputting images for OCR by performing a binarization process on the image after it has been monochromatized, and then outputting it as a binary image.

[0107] Figure 21 shows an example of the configuration according to modified example 10. As shown in Figure 21, the image correction unit 33 is provided with a binarization processing unit 39.

[0108] The binarization processing unit 39 performs a binarization process on the monochromatized image output from the monochromatization processing unit 35, and outputs a binary image as a monochromatized image.

[0109] Outputting a binary image in this way has the effect of reducing the amount of data. Furthermore, by performing the binarization process within the image correction unit 33, it is possible to perform binarization with parameters suitable for the reading device. In this case, even if the binarization process provided by the subsequent OCR software is of low accuracy, the reading device performs the binarization and passes the data, so it is possible to improve the OCR recognition rate regardless of the accuracy of the binarization provided by the OCR software.

[0110] Furthermore, although Figure 21 shows a single-image output configuration with only a monochrome image, it can also be applied to outputting multi-image images including RGB images, as shown in Figure 10.

[0111] (Second Embodiment) The image processing device may perform some or all of the processing for removing imprints from visible images that is performed by the reading device 1 or external device as shown in the first embodiment.

[0112] Figure 22 shows an example of the configuration of a system including an image processing device according to the second embodiment. The image processing device 2 takes the visible image and invisible image output by the reader 1 as input and performs processing for seal impression removal. Alternatively, the image processing device 2 may acquire the visible image and invisible image stored in the server SS and perform processing for seal impression removal. Alternatively, the image processing device 2 may read the visible image and invisible image from a portable storage medium DA such as a semiconductor memory and perform processing for seal impression removal.

[0113] The image processing device 2 is equipped with a CPU, which executes a predetermined program to perform functions corresponding to the processing unit 30 and the black character area determination unit 32, as well as various functions such as image mark removal and OCR processing. Some or all of these functions may be implemented by hardware such as an ASIC (Application Specific Integrated Circuit). The image processing device 2 outputs various images from its output unit to an external device such as a PC.

[0114] Since the various functions have already been explained in the first embodiment using the reading device and external device as examples, further explanation will be omitted here.

[0115] (Third embodiment) The reading device shown in the first embodiment and the image processing device shown in the second embodiment may be mounted on an image forming apparatus.

[0116] Figure 23 shows an example of the configuration of an image forming apparatus according to the third embodiment. Figure 23 shows an image forming apparatus 3, generally referred to as a multifunction printer (MFP), as an example. The image forming apparatus 3 shown in Figure 23 is equipped with a reading device (reading device body 10 and ADF 20) at the top. The configuration of the reading device will be repeated from the description of the first embodiment, so a detailed explanation will be omitted here.

[0117] The image forming apparatus 3 shown in Figure 23 has an image forming section 80 and a paper feeding section 90 located below the reading device body 10.

[0118] The image forming unit 80 prints the image read by the reading device body 10 onto recording paper, which is an example of a recording medium. The read image is either a visible image or a near-infrared image.

[0119] The image forming unit 80 includes an optical writing device 81, tandem image forming units (Y, M, C, K) 82, an intermediate transfer belt 83, a secondary transfer belt 84, and the like. In the image forming unit 80, the optical writing device 81 writes the image to be printed onto the photoreceptor drum 820 of the image forming unit 82, and then transfers the toner images of each plate from each photoreceptor drum 820 onto the intermediate transfer belt 83. The K plate is formed with K toner containing carbon black.

[0120] The imaging unit (Y, M, C, K) 82 has four rotatable photoreceptor drums (Y, M, C, K) 820, and each photoreceptor drum 820 is surrounded by imaging elements including a charging roller, a developer, a primary transfer roller, a cleaner unit, and a static eliminator. Each imaging element operates around each photoreceptor drum 820 in a predetermined imaging process, forming an image on each photoreceptor drum 820, and the images formed on each photoreceptor drum 820 are transferred as toner images onto the intermediate transfer belt 83 by the primary transfer roller.

[0121] The intermediate transfer belt 83 is positioned and stretched by a drive roller and a driven roller in the nip between each photoreceptor drum 820 and each primary transfer roller. The toner image primary transferred to the intermediate transfer belt 83 is then secondary transferred to the recording paper on the secondary transfer belt 84 by the secondary transfer device as the intermediate transfer belt 83 moves. The recording paper is then transported to the fuser device 85 as the secondary transfer belt 84 moves, and the toner image is fixed onto the recording paper. After that, the recording paper is discharged to the output tray outside the machine.

[0122] The recording paper is supplied to the secondary transfer belt 84 by, for example, the paper feeding unit 90, which feeds a predetermined amount of recording paper from paper feed cassettes 91 and 92 that store recording paper of different sizes, and transports it using a transport means 93 consisting of various rollers.

[0123] Furthermore, the image forming unit 80 is not limited to forming images by the electrophotographic method described above, but may also form images by an inkjet method. Furthermore, the image forming apparatus is not limited to an MFP (Multifunction Printer). The image forming apparatus may also be, for example, a printer that receives image data generated by a separate image processing device via communication and prints the received image data.

[0124] While embodiments and variations of the present invention have been described above, these embodiments and variations are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments and variations can be implemented in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents.

[0125] Examples of the present invention are as follows: <1> An input unit that receives visible image data read by a sensor sensitive to light from a light source in the visible wavelength range and invisible image data read by a sensor sensitive to light from a light source in the invisible wavelength range of the subject, An image processing unit that generates image data in which the portion of the visible image data that corresponds to a specified region, which is the portion of the invisible image data with an absorption rate of a predetermined value or higher, is displayed in a specified color. An image processing device having <2> The system further includes an output unit that outputs the image data generated by the image processing unit to an external device. <1> The image processing device described above. <3> The output unit outputs the visible image data of the subject and the image data generated by the image processing unit to the external device. <2> The image processing device described above. <4> A specified color removal unit removes a specified color from the image data generated by the image processing unit, A monocolor processing unit that performs monocolorization on the image data after the removal of the specified color, It further possesses, The output unit outputs the image data after the monochrome processing to the external device. <2> or <3> The image processing device described above. <5> The specified color removal unit removes the specified color set by the user from the image data generated by the image processing unit. <4> The image processing device described above. <6> The monochromatized image data from the aforementioned monochromatization processing unit is output as multi-level image data. <4> or <5> The image processing device described above. <7> The monochromatic processing unit outputs binary image data by binarizing the monochromatic image data. <4> or <5> The image processing device described above. <8> It has a designation unit that identifies a portion with an absorption rate of a predetermined value or higher as a designated region based on the aforementioned invisible image data, The specified unit determines the designated region by binarizing the invisible image data. <1> ~ <7> An image processing device as described in one of the following. <9> The specified part is, It has a threshold determination unit that determines a threshold based on the set scalp level and black level, The binary processing is performed based on the threshold determined by the threshold determination unit. <8> The image processing device described above. <10> The threshold determination unit, A scalp level detection unit for detecting the scalp level of the visible image data of the subject, A black level detection unit that detects the black level of the visible image data of the subject, It has, Based on the scalp level detected by the scalp level detection unit and the black level detected by the black level detection unit, the threshold corresponding to each region of the visible image data of the subject is determined. <9> The image processing device described above. <11> The aforementioned image processing unit, It has a luminance color difference conversion unit that converts RGB image data into luminance color difference data, The unit includes an RGB conversion unit that processes a luminance color difference signal to display the portion of the visible image data corresponding to the specified area in the specified color, and then converts the processed signal data back into RGB image data. <1> ~ <10> An image processing device as described in one of the following. <12> The image processing unit adjusts the output value of the luminance component of the luminance signal according to the luminance component adjustment setting value set by the user. <11> The image processing device described above. <13> The image processing unit sets the specified color for displaying the portion of the visible image data corresponding to the specified area to black. <1> ~ <12> An image processing device as described in one of the following. <14> <1> ~ <13> An image processing device described in any one of the following, A visible light source that irradiates the subject with visible wavelength light, An invisible light source that irradiates the subject with light of an invisible wavelength, A first image sensor that receives visible wavelength reflected light from the subject and outputs visible image data, A second image sensor receives invisible wavelength reflected light from the subject and outputs invisible image data, A reading device having [a certain feature]. <15> The aforementioned image processing unit, The invisible image data output by the second image sensor and the visible image data output by the first image sensor are input. <14> The reading device described in [reference]. <16> <1> ~ <13> An image processing device described in any one of the following, <14> or <15> The reading device described above, An image forming unit that forms an image based on the image data generated by the image processing unit, An image forming apparatus having <17> <3> or <4> The image processing apparatus described above, An information processing device that manages the visible image data transmitted from the image processing device and the image data generated by the image processing device by linking them together. A data management system that has the following features. <18> A method for image processing visible image data obtained by reading a subject with a sensor sensitive to light from a light source in the visible wavelength range, The steps include inputting the visible image data of the subject and invisible image data obtained by reading the subject with a sensor sensitive to light from a light source in the invisible wavelength range, The steps include generating image data that displays in a specified color the portion of the visible image data that corresponds to a specified region, which is the portion of the invisible image data that has an absorption rate greater than or equal to a predetermined value, in the visible image data; A method that includes this. <19> An input unit that receives visible image data read by a sensor sensitive to light from a light source in the visible wavelength range and invisible image data read by a sensor sensitive to light from a light source in the invisible wavelength range of the subject, An image processing unit that generates image data in which the portion of the visible image data corresponding to the specified region of the invisible image data that contains carbon as a material is displayed in a specified color. An image processing device having [Explanation of symbols]

[0126] 00 Image Processing Device 1a Input section 2a Image Processing Unit 3a Specific part Output section of 4a 13-1 Visible light source 13-2 Near-infrared light source 17-1 Visible Image Sensor 17-2 Near-infrared image sensor 30-1 Achromatic part 31 Decolorization Treatment 32 Black text area determination unit 40 Imaging Unit D1 Visible Image Data D2 Invisible Image Data D3 image data [Preliminary Technology Documents] [License]

[0127] [License 1] Special Announcement No. 11-205618

Claims

1. An input unit that receives visible image data read by a sensor sensitive to light from a light source in the visible wavelength range and invisible image data read by a sensor sensitive to light from a light source in the invisible wavelength range of the subject, An image processing unit that generates image data in which the portion of the visible image data that corresponds to a specified region, which is the portion of the invisible image data with an absorption rate of a predetermined value or higher, is displayed in a specified color. An image processing device having

2. The system further includes an output unit that outputs the image data generated by the image processing unit to an external device. The image processing apparatus according to claim 1.

3. The output unit outputs the visible image data of the subject and the image data generated by the image processing unit to the external device. The image processing apparatus according to claim 2.

4. A specified color removal unit removes a specified color from the image data generated by the image processing unit, A monocolor processing unit that performs monocolorization on the image data after the removal of the specified color, It further possesses, The output unit outputs the image data after the monochrome processing to the external device. The image processing apparatus according to claim 2.

5. The specified color removal unit removes the specified color set by the user from the image data generated by the image processing unit. The image processing apparatus according to claim 4.

6. The monochromatized image data from the aforementioned monochromatization processing unit is output as multi-level image data. The image processing apparatus according to claim 4.

7. The monochromatic processing unit outputs binary image data by binarizing the monochromatic image data. The image processing apparatus according to claim 4.

8. It has a designation unit that identifies a portion with an absorption rate of a predetermined value or higher as a designated region based on the aforementioned invisible image data, The specified unit determines the designated region by binarizing the invisible image data. The image processing apparatus according to claim 1.

9. The specified part is, It has a threshold determination unit that determines a threshold based on the set scalp level and black level, The binary processing is performed based on the threshold determined by the threshold determination unit. The image processing apparatus according to claim 8.

10. The threshold determination unit, A scalp level detection unit for detecting the scalp level of the visible image data of the subject, A black level detection unit for detecting the black level of the visible image data of the subject, It has, Based on the scalp level detected by the scalp level detection unit and the black level detected by the black level detection unit, the threshold corresponding to each region of the visible image data of the subject is determined. The image processing apparatus according to claim 9.

11. The aforementioned image processing unit, It has a luminance color difference conversion unit that converts RGB image data into luminance color difference data, The system includes an RGB conversion unit that processes a luminance color difference signal to display the portion of the visible image data corresponding to the specified area in the specified color, and then converts the processed signal data back into RGB image data. The image processing apparatus according to claim 1.

12. The image processing unit adjusts the output value of the luminance component of the luminance signal according to the luminance component adjustment setting value set by the user. The image processing apparatus according to claim 11.

13. The image processing unit sets the specified color for displaying the portion of the visible image data corresponding to the specified area to black. The image processing apparatus according to claim 1.

14. An image processing apparatus according to any one of claims 1 to 13, A visible light source that irradiates the subject with visible wavelength light, An invisible light source that irradiates the subject with light of an invisible wavelength, A first image sensor that receives visible wavelength reflected light from the subject and outputs visible image data, A second image sensor receives invisible wavelength reflected light from the subject and outputs invisible image data, A reading device having [a certain feature].

15. The aforementioned image processing unit, The invisible image data output by the second image sensor and the visible image data output by the first image sensor are input. The reading device according to claim 14.

16. An image processing apparatus according to any one of claims 1 to 13, An image forming unit that forms an image based on the image data generated by the image processing unit, An image forming apparatus having

17. The image processing apparatus according to claim 3 or 4, An information processing device that manages the visible image data transmitted from the image processing device and the image data generated by the image processing device by linking them together. A data management system that has the following features.

18. A method for image processing visible image data obtained by reading a subject with a sensor sensitive to light from a light source in the visible wavelength range, The steps include inputting the visible image data of the subject and invisible image data read from the subject by a sensor sensitive to light from a light source in the invisible wavelength range, The steps include generating image data that displays in a specified color the portion of the visible image data that corresponds to a specified region, which is the portion of the invisible image data that has an absorption rate greater than or equal to a predetermined value, and A method that includes this.

19. An input unit that receives visible image data read by a sensor sensitive to light from a light source in the visible wavelength range and invisible image data read by a sensor sensitive to light from a light source in the invisible wavelength range of the subject, An image processing unit that generates image data in which the portion of the visible image data corresponding to the specified region of the invisible image data that contains carbon as a material is displayed in a specified color. An image processing device having

Images